The x402 protocol enables instant Blockchain payments over HTTP using the 402 "Payment Required" status code. This is your complete guide to mastering x402 and building the future of agent payments.
Core resources from the x402 protocol maintainers.
Essential documentation for understanding and implementing x402.
Get started with x402 in minutes.
Official and community implementations of the x402 protocol.
Real companies using x402 in production with proven scale and transaction volumes.
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Pyrimid - Agent commerce protocol for x402-style USDC payments on Base. Includes on-chain vendor/product registry, payment router, affiliate attribution, MCP endpoint, and live catalog API for agent-discoverable paid services. Current mainnet proof: 3 vendors, 8 on-chain products, 4 routed test payments. (Catalog) (MCP) (Skill)
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Polybot Arb Intelligence — Real-time cross-platform prediction market arb data (Polymarket+Kalshi+Myriad). x402 USDC on Base. Live API
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Aigregator - Structured data on 5,336+ AI tools via REST API and MCP server. Search, compare, and retrieve tool profiles. USDC micropayments on Base. (MCP Server)
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Xquik - Real-time X (Twitter) data API with 7 MPP/x402 pay-per-use endpoints — tweet lookup, tweet search, user lookup, follower check, article extraction, media download, and trends. No accounts or subscriptions required. (GitHub) (npm) (MCP Server)
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agentsvc.io - 20 utility tools for AI agents via x402 USDC micropayments on Base. Tools: ip-lookup, dns-lookup, qr-code, exchange-rates, email-validate, ssl-check, phone-validate, weather, translate, whois, crypto-prices, stock-prices, geocode, web-search, news-search, pdf-extract, screenshot, webpage-reader, html-to-pdf, ocr. $0.001–$0.008 USDC per call. No API keys, no signup. Auto-discovery: /.well-known/agent-services.json | Catalog | OpenAPI | MCP Server | (GitHub)
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AgentData API - Real-time crypto market data for AI agents. 16 pay-per-request endpoints on Base Mainnet: prices, funding rates, volatility, liquidation levels, DeFi yields, cross-exchange arbitrage, technical indicators (RSI/MACD/BB/ATR), support/resistance, sentiment, stablecoin health, and historical OHLCV. Self-hosted facilitator, no accounts required. Supports x402 v2 with Bazaar discovery extension. (Discovery) (OpenAPI)
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Fly Labs Agentic Market - YouTube data APIs for AI agents, paid in USDC on Base. Two endpoints live: POST /api/agents/transcribe ($0.03) returns a stable v1.0 JSON payload with verbatim transcript, language, time-indexed paragraphs, creator chapters, and canonical metadata (captions when available, Whisper fallback otherwise, no LLM rewrites). POST /api/agents/engagement ($0.02) returns view/like/comment counts, derived ratios, a composite engagement score, channel info (subscribers included), and full video context (tags, categories, thumbnail, availability, live status). Transparent cache on every response (cache.hit, cachedAt, ageSec) — transcripts are permanent, engagement refreshes every 6 hours. Typed error codes, OpenAPI 3.1, no signup. (OpenAPI 3.1) (Manifest)
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NicheData KDP Intelligence - Niche demand and competition intelligence for Kindle Direct Publishing authors. AI agents query keyword-level data including demand scores, competition intensity, BSR ranges, revenue estimates, and pricing analytics. $0.03 USDC per query on Base via CDP Facilitator. Free discovery endpoint lists all available niches. (OpenAPI) (Docs)
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DevDrops - 22 pay-per-query data APIs for AI agents — prediction markets (Polymarket + Manifold), property intelligence, sports odds, regulatory filings, FX rates, weather, IP geolocation, academic papers, document summarisation (Claude), and more. $0.001–$0.10 USDC per query on Base. No API keys or subscriptions. (OpenAPI) (Catalog)
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Social Intel — Instagram influencer search API for AI agents. Search by niche, country, demographics, or follower count → returns usernames, bios, follower counts, business categories, and public business emails. Single-profile lookup at $0.01; full search $0.50–$1.30 (100 leads). USDC on Base, Solana, Polygon, Arbitrum. No signup. (OpenAPI) (MCP Server) (Demo)
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GlobalAPI - Compliance and macro-economics API hub for AI agents across 43 endpoints. Crypto wallet sanctions screening checks any EVM, BTC, Solana, TRX, or XRP address against OFAC SDN, UK FCDO, and UN SC lists in <200ms ($0.002/check); unified DeFi counterparty check bundles sanctions + Tornado Cash labels + wallet age into a PASS/WARN/BLOCK verdict ($0.01). Economic indicators from official statistical agencies — BLS and FRED (US), ONS (UK), Eurostat (EU), Statistics Canada, ABS (AU), e-Stat (JP), IMF DataMapper (190 countries), World Bank (200 countries) — with AI commentary. Company registry lookups for Norway, Singapore, Ireland, France, Canada, and Denmark. No API key — x402 USDC on Base mainnet, $0.002–$0.10/call. (OpenAPI | Discovery)
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TOUGH LOVE SECURITY ImageGen - Pay-per-image AI generation powered by Cloudflare Workers AI (Stable Diffusion XL Lightning + Flux-1-Schnell). Three tiers: $0.50 single, $1.99 12-pack, $7.99 100-bundle. Stripe Checkout for humans, x402 for agents at $0.04/image. No accounts, no expiring credits. (Launch post)
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TOUGH LOVE SECURITY ClawWork - Instant AI labor marketplace with three tiers: $5 quick polish (90s turnaround), $25 deep brief (1.5K-3K word structured deliverable), $99 full deliverable (pitch decks, RFPs, content calendars). Stripe + x402 ($0.05/call on bulk). Powered by Claude 4.7 Sonnet. (Launch post)
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TOUGH LOVE SECURITY Contract Risk Score - Smart contract risk scoring API for DeFi devs. Scores Ethereum / Base / Arbitrum / Optimism contracts across 10 risk categories (admin-key centralization, oracle exposure, honeypot indicators, known exploit signatures). $1.25 per 5-pack via Stripe, $0.25/call via x402. Triage layer between "free Etherscan glance" and "$50K formal audit." (Launch post)
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Deepnets - Solana token intelligence: safety analysis, deep wallet-funding-network mapping, holder breakdowns, social/Twitter research, trending feed, streamflow/staking lockup data. 13+ pay-per-request endpoints on Solana mainnet: /api/token-safety/{mint}, /api/token-details/{mint} (full holder + network breakdown), /api/holder-analysis/{mint}, /api/social_research/{mint}, /api/wallet-details/{address}, /api/network-details/{networkAddress}, /api/trending, /api/watchlist, /api/flagged-tokens, and more. $0.01 basic / $0.15 holder analysis. USDC on Solana, gas sponsored by the facilitator — no SOL needed. v2 with Bazaar discovery extension. (OpenAPI) (Docs) (Marketing)
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OpenPulsechain - PulseChain blockchain analytics API with 28 x402-paid endpoints: token safety scores (0-100), opportunity signals, whale alerts, pair analytics (price impact, volatility), deployer reputation, AML funding tree, smart money feed, gas price, OHLCV history. Covers 5,900+ tokens. $0.001–$0.03 USDC per call on Base. (x402 Discovery) (npm MCP) (GitHub)
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DataFood (TOUGH LOVE SECURITY) - Universal data hub for AI agents — 17 cross-niche sources (crypto prices, ETH gas, weather, news, HN, GitHub trending, DeFi yield, token risk via GoPlus, HHS healthcare-breach feed, geocoding, more) behind one POST /api/data/bundle call. Bundle micropayments save up to 92% vs per-API alternatives. Day pass $0.99 unlimited 24h, week pass $4.99. Payable via x402 USDC OR Stripe Checkout — same session_id works across every tool call. Free 1-row preview at /api/data/preview?type=…&q=…. (Live demo) (MCP server) (x402 descriptor) (catalog)
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Askew - Security and DeFi intelligence for AI agents. 5 pay-per-call endpoints on Base mainnet: /yields ($0.002, live APY across 5 chains via DefiLlama), /staking/router ($0.003, SOL/ATOM native vs liquid staking routing), /research/query ($0.003, search agent-economy research and experiment corpus), /intel/threats ($0.002, Guardian security threat summary), /intel/feed ($0.005, combined research + threats + staking strategic feed). Free preview at /yields/preview and /health. Self-hosted facilitator (xpay.sh). Auto-discovery: (/.well-known/x402.json | llms.txt | /offers)
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BitBooth - 6 utility, content, and security endpoints for AI agents on Base mainnet, settling via Coinbase CDP Facilitator. Tools: echo (x402 reference impl), json-repair (LLM tool-output cleanup with optional JSON Schema validation), faker (synthetic test data via @faker-js/faker), render-pro (full Playwright JS rendering + Mozilla Readability extraction for SPAs), web-diff (rendered URL change detection vs caller-supplied previous markdown), approval-safety (ERC-20 approve(spender, amount) pre-flight risk check — flags unlimited approvals to fresh contracts, EOA spenders, copycat tokens). $0.001 USDC per call for utility tier, $0.05 for premium tier. No API keys, no subscriptions. Self-hosted discovery at bazaar.json. (GitHub)
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EconDash - Global macroeconomic data API for AI agents: 753 indicators across 298 countries (World Bank, FRED, OECD). 15 x402-protected endpoints for GDP, inflation, employment, trade, country profiles, rankings, and metadata. $0.02 USDC/call on Base. Also supports MPP (Tempo + Solana). (Docs) (OpenAPI)
Client libraries for making x402 payments.
Server-side integrations for accepting x402 payments.
Payment verification and settlement services.
Full working examples and templates.
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Daizyx402 Security Research API - AI-powered smart contract security analysis and DeFi vulnerability research by autonomous agent. $0.05 USDC per query, $0.50 USDC deep analysis on Base mainnet. No signup required.
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tx402.ai - Agent-native LLM inference gateway. 20+ EU-hosted models (DeepSeek, Qwen, Llama, GLM, Mixtral) via x402 USDC micropayments on Base. OpenAI-compatible API, SSE streaming, GDPR-compliant, zero data retention. No API keys — wallet is auth. Models | OpenAPI | llms.txt | Source
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SolSignal API - Solana token safety scanner — aggregates DexScreener, RugCheck, GoPlus & Jupiter simulation into one SAFE/CAUTION/AVOID/RUG verdict in <2s. 10 free scans/day, $0.01 USDC per call on Solana. Source
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x402 Gateway - Simple Node.js API gateway for AI agents. Weather ($0.01), crypto prices ($0.01), exchange rates ($0.005), news ($0.02). USDC on Polygon. HTTPS via Cloudflare Tunnel. Source
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Alfred's Digital Bazaar - ~100 x402-paywalled API endpoints built by an AI agent. Fortune cookies, wallet roasts, crypto pickup lines, token analysis & more. $0.10–$1.00 USDC per call on Base. No signup required. Source
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Banking Bodyguard - Real-time cbBTC whale movement signals on Base. Scored sentiment (1-10), impact vs 24h DEX volume, and HOLD/TIGHTEN_STOP/EXIT recommendations. ~500K signals indexed. x402 enforced — $0.10 USDC per call on Base. Docs
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Solana Trading Data API - Real-time Solana ecosystem data for AI agents. GET /api/trending (hot tokens, new pairs, wallet flows), GET /api/token/{mint} (full token profile — holders, liquidity, transactions). x402 gated at $0.01 USDC per call on Solana mainnet. .well-known/x402 | .well-known/agent-card.json | Source
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Gotobi Calendar API - Japanese FX gotobi date intelligence for trading agents. Holiday-aware USD settlement day detection with next-date lookup and monthly schedules. $0.01 USDC on Base and Solana. Source
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Weather API - Global weather data for AI agents. Real-time conditions and 7-day forecasts. $0.01 USDC on Base. Source
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Micro Data API Factory — Weather - Cloudflare Workers edge weather for AI agents. Instant data by city name — no API keys, no geocoding setup, no rate limits. Current conditions + 1-7 day forecasts worldwide. 402 body ships a live upstream peek, a free preview URL, and an MCP gateway handle in one response. $0.001 USDC per call on Base. Open-Meteo (CC BY 4.0). .well-known/x402 | llms.txt | MCP gateway
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Micro Data API Factory — Broker - Wallet-free entry layer for the Micro Data API Factory products. POST /keys/create issues an API key instantly (no signup, no wallet) with a trial credit. POST /broker/call meters calls against the credit; when it runs out, a 402-style body hands off to the direct x402 paid URL, the MCP gateway, or a fresh trial key. Factory primitive — new products are added by DB insert, not redeploy. Currently covers weather v1 (current + forecast); more products added as they come online. manifest | llms.txt | products
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Micro Data API Factory — JP Local Pack - Japan backoffice primitives for AI agents: payroll summary, payroll deductions, social-insurance grade lookup, consumption tax, holidays, corporate-number lookup, invoice issuer lookup, invoice registration lookup, and Peppol validation through one gateway. Wallet-free preview routes live under /preview/v1/local/...; x402-paid production routes live under /v1/local/... on Base USDC. $0.001-$0.02 USDC per call. Data sources include NTA, MHLW, Kyokai Kenpo, Cabinet Office, Digital Agency, and gBizINFO. products | llms.txt | openapi
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Micro Data API Factory — JP Grants - Japan grants deadline tracker and review-required candidate triage for AI agents. Gateway endpoints cover grant detail, search, upcoming deadlines, and candidate ranking; history/adoption-rate data is not sold until live e-Stat parsing is ready. Wallet-free preview routes live under /preview/v1/grants/...; x402-paid production routes live under /v1/grants/... on Base USDC. $0.02-$0.05 USDC per call. Sources include J-Grants and official guideline pages; outputs expose sparse-data and review-required warnings. products | llms.txt | openapi
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Micro Data API Factory — JP Data Enrich - Japan public-company and supplier intelligence for AI agents. Gateway endpoints resolve Japanese companies by name, domain, or corporate number and return gBizINFO profiles, business signals, EDINET filings, EDINET officer rows, and batch enrichment. Wallet-free preview routes live under /preview/v1/enrich/...; x402-paid production routes live under /v1/enrich/... on Base USDC. $0.01-$0.05 USDC per call. Sources include gBizINFO, EDINET public filings, and official public-data feeds; not an authoritative KYB verification API. products | llms.txt | openapi
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Micro Data API Factory — Kasanegi API Gateway - x402 gateway for AI agents buying Japan business-data micro-APIs through one host: JP Local Pack (backoffice primitives), JP Data Enrich (public-company and supplier intelligence), and JP Grants (deadline tracker + review-required candidate triage). Wallet-free preview routes live under /preview/v1/...; x402-paid production routes live under /v1/... on Base USDC. $0.001-$0.05 USDC per call. portal | products | llms.txt | openapi
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Scout MCP - Multi-source search across code, academic, social, and community platforms. One call returns structured JSON. From $0.01 USDC on Base; $0.25 for aggregated reports. Source
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Obol — AI code generation via x402. Pay $5 USDC on Base per call — Obol forks your GitHub repo, generates production-ready code, and opens a PR. 7 endpoints: Next.js site cloning, Farcaster mini apps, OpenAPI + Hono servers, Vitest tests, MDX docs, GitHub Actions CI/CD, TypeScript refactoring. A2A agent card + OpenAPI discovery built-in. API
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ShieldAPI MCP - 9-tool security MCP server: password breach, email breach, domain reputation, IP reputation, URL safety, full security scan, prompt injection detection, and skill security scanning. x402 USDC micropayments on Base or free demo mode. npx shieldapi-mcp. (GitHub)
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Mailcheck API - Email validation: syntax, MX records, disposable domain detection, free provider check, role-based address detection, and typo suggestion. $0.01 USDC on Base. Source
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DeFi Intelligence API - Unified DeFi security, bridging, and analytics for AI agents. 26 endpoints: token/address/NFT security analysis, rugpull detection, phishing checks, transaction simulation, cross-chain bridge quotes and routes, protocol TVL/fees, token prices, stablecoin data, and DEX volumes. Integrates GoPlus Security + LI.FI + DeFi Llama. $0.005–$0.01 USDC per call on Base.
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Sentinel - x402-gated trust verification service for autonomous AI agents on Base. Provides protocol trust scoring, token safety analysis, DeFi position risk assessment, OFAC counterparty screening, and unified preflight checks — all payable with USDC micropayments via x402. 5 endpoints: /verify/protocol ($0.008), /verify/token ($0.005), /verify/position ($0.005), /verify/counterparty ($0.010), /preflight ($0.025). Integrates DeFiLlama, GoPlus Security, Etherscan, Alchemy, and OFAC SDN. Includes .well-known/x402 discovery, OpenAPI spec, and Bazaar extensions. (GitHub)
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Domain Intelligence API - Domain analysis for AI agents. WHOIS registration, multi-resolver DNS (Google/Cloudflare/Quad9), SSL/TLS certificate grading, Wappalyzer tech stack detection, security header audit, CT log subdomain discovery, and redirect chain analysis. 8 endpoints from $0.001 USDC on Base. llms.txt
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Visual API - Screenshot, PDF capture, and document parsing for AI agents. Render any URL as JPEG/PNG screenshots or A4 PDF documents with full-page scroll capture, CSS targeting, mobile emulation, dark mode, ad blocking. Parse uploaded PDFs into structured text with metadata. $0.01–$0.02 USDC per call on Base.
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Whale Intelligence API - On-chain whale tracking for AI agents. 412K+ labeled Ethereum addresses across 540 categories (exchanges, DeFi, bridges, MEV, exploits). Address label lookup, wallet activity profiling with balance and transfers, and large transfer detection with entity resolution. $0.01–$0.02 USDC per call on Base. llms.txt
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COT Intelligence API - CFTC Commitments of Traders data for FX trading agents. Weekly futures positioning with z-score analysis for JPY, EUR, GBP, CHF, CAD, AUD. Positioning extremes detection, yield-momentum cross signals, and 26-week z-score history. $0.01–$0.02 USDC per call on Base. llms.txt
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Polymarket Intelligence API - Prediction market anomaly signals for AI agents. Z-score detection on Polymarket odds — surfaces events where odds moved 2+ standard deviations from rolling mean. Covers fed rates, crypto prices, regulation, geopolitics, tariffs. $0.01 USDC per call on Base. llms.txt
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Sanctions Screening API - OFAC, EU, and UN Security Council sanctions screening for AI agents. 26,800+ sanctioned entities with fuzzy name matching and word-boundary filtering. Screen names or search with source filtering. $0.01 USDC per call on Base. llms.txt
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CVE Intelligence API - NVD vulnerability lookup, search, and recent CVEs for AI agents. CVSS v3.1/v4.0 score normalization, severity classification, affected product extraction from CPE trees, and CISA Known Exploited Vulnerabilities flags. $0.01 USDC per call on Base. llms.txt
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FDA Intelligence API - OpenFDA drug and device safety intelligence for AI agents. Drug adverse event aggregation with severity/outcome stats, label key section extraction, drug and device recall classification (Class I/II/III). 4 endpoints at $0.01 USDC per call on Base. llms.txt
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Nutrition Intelligence API - USDA FoodData Central nutrition data for AI agents. Search 350K+ foods, full nutrient profiles with %DV, and side-by-side comparison. Macros, vitamins, minerals categorized. $0.01 USDC per call on Base. llms.txt
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EDGAR Intelligence API - SEC EDGAR corporate filing intelligence for AI agents. Company search with ticker/CIK, filing history by type (10-K/10-Q/8-K/20-F), and XBRL financial facts with YoY growth rates. Revenue, net income, EPS, assets. $0.01 USDC per call on Base. llms.txt
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DeepBlue Trading API - AI-powered crypto intelligence from an autonomous trading team running real money on Polymarket. 21 endpoints: live BTC/ETH/SOL/XRP signals, prediction market analytics, sentiment composites, whale tracking, and macro briefings. $0.01–$0.05 USDC per call on Base. OpenAPI
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MoonMaker API - AI-native crypto data API with x402 pay-per-call. 11 endpoints: signals, market context, DeFi regime, institutions, ETF flows, DeFi yields, DEX alpha. $0.02–$0.10/call USDC on Base. No signup. llms.txt
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DeFi Signal Agent - Real-time DeFi intelligence for AI agents. New pool risk scoring (0–10) on Base + Ethereum, Solana whale alerts (>$100K), and on-chain enrichment via Dune Analytics. 4 endpoints from $0.01–$0.10 USDC per call on Base Sepolia. Self-hostable. Source
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x402 AI API — zeroreader - 29 Cloudflare Workers AI models (LLM, Embeddings, Image Generation, Audio, Translation) via x402 micropayments. $0.001–$0.015 per request, USDC on Base. Supports streaming, batch processing, OpenAI-compatible format. llms.txt | OpenAPI
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Content Intelligence API - AI-powered web content extraction and analysis for AI agents. Clean text extraction with trafilatura (F1=0.909), metadata/OG tags, link classification, AI summarization with key points and entity extraction, full sentiment/topic/credibility analysis via Gemini. 5 endpoints from $0.003 USDC on Base.
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Intel API - AI-synthesized token due diligence reports for crypto assets. Aggregates 4 GoPlus security checks + CoinGecko market data into risk-scored verdicts with red/green flags and recommendations. One call replaces 5+ separate security APIs. $0.50 USDC per call on Base.
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Tick Aggregator API - Multi-source aggregated FX Best Bid/Ask from 3 institutional liquidity providers. 62-88% tighter spreads than any single source. 15 pairs including EURUSD, USDJPY, GBPUSD, XAUUSD. Returns quality metadata (fresh sources, spread improvement vs single source). Commercial use permitted. $0.005 USDC per call on Base and Solana. llms.txt
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REST API with Auth Pricing - SIWE + dynamic pricing.
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geo-gateway - Pay-per-call Mapbox geospatial proxy for AI agents. 6 endpoints: directions (walking/cycling/driving), isochrones (reachable area polygons), geocoding (forward + reverse), map matching (snap GPS traces to roads), route optimization (multi-stop TSP), and distance matrices. Pre-payment validation so bad requests are never charged. $0.002–$0.0635 USDC per call on Base. OpenAPI | Source
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PortsideLabs Places API - Google Places API v1 proxy with x402 pay-per-request access. Exposes place detail lookup and full-text search via USDC micropayments on Base mainnet and Solana mainnet. $0.001 USDC per call.
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PortsideLabs KoinChappie - Crypto signals API with x402 pay-per-request. Returns bull and bear signals for the top 10 cryptocurrencies by market cap across 8 timeframes (1m–1D) using SMA(14). Single-coin lookup supports any CryptoCompare symbol. USDC micropayments on Base mainnet and Solana mainnet. $0.001 USDC per call.
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CYBERA Compliance API - Crypto compliance suite for AI agents. VASP address identification (20,468 addresses, 29 chains), risk scoring (0-100 with signal detection), and sanctions/mixer screening (single + batch). Three endpoints at $0.01 USDC per call on Base. Source | llms.txt
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Kerdos Market Intelligence - AI market intelligence API for agents and traders. 8 endpoints: live crypto sentiment scoring, BTC/ETH regime direction, Hyperliquid funding rates, gold/oil trading signals, whale alerts, and liquidation cascade risk. $0.01-$0.05 USDC per call on Base.
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Mercury402 - Pay-per-call U.S. Treasury and macro data API using x402. Agents access FRED indicators, yield curves, and GDP data with USDC micropayments on Base.
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Product Reputation API — AI-powered product reputation intelligence from Reddit, HN & YouTube. Pay $0.03-$0.08 USDC per query for structured scores, dimensional analysis, and competitor comparisons. (Live) (x402scan)
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x402engine - Pay-per-call API gateway with 74 endpoints: 44 LLMs, image/video generation, crypto data, web search, code execution, TTS, travel, and IPFS. Multi-chain: USDC on Base, USDm on MegaETH, USDC on Solana. Discovery: /.well-known/x402.json | /.well-known/agent.json. (GitHub) | (MCP)
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SignalFuse — Trading intelligence + x402 API gateway. Crypto signals fusing sentiment, macro regime, and market structure ($0.001–$0.050). Gateway proxies: web search via Tavily ($0.012) and Brave ($0.008), code execution via E2B ($0.005). Agents pay USDC on Base per call — no API keys needed. Landing | Gateway Info
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mornin-agentee — Daily Tokyo morning briefing API generated by an OpenClaw multi-agent system (researcher + coder + main). Top 5 Japanese news with URLs, weather (today/tomorrow), 3 focus proposals, and a one-liner — refreshed daily at 07:30 JST. $0.05 USDC per call on Base mainnet. Cached output (near-zero marginal cost). llms.txt | .well-known/x402.json | Source
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cipher-mcp-registry - x402-gated search for the Official Model Context Protocol Registry. Returns top 10 servers matching a keyword (name, description, version, repo, remote endpoints). $0.005 USDC/Base per call.
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cipher-gas-oracle - x402-gated multi-chain gas oracle. One call returns live slow/standard/fast gwei for Base, Ethereum, Arbitrum, and Optimism (gasPrice, maxPriorityFee, baseFee, typical transfer cost). $0.005 USDC/Base per call.
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Rug Scanner - On-chain token risk analysis API. 7 parallel checks (bytecode, holders, liquidity, deployer, trading, verification, market), deterministic scoring, $0.05 USDC per scan via x402 on Base. (GitHub)
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agent-marketplace-proxy - x402-gated Google SERP API. POST /search returns top organic results from DataForSEO; agents pay $0.001 USDC per call on Base — no API key, no signup, no credit card. Single-route reference implementation showing how to wrap any commodity REST API with x402-express middleware in ~80 lines. (Source)
Real-world use cases and implementation patterns. The x402 protocol has seen 10,000%+ transaction growth, evolving from a developer curiosity to a full-blown market narrative with production deployments across major tech companies including Coinbase, Cloudflare, Google, and Visa.
Enable AI agents to make autonomous payments.
x402-native GPU inference APIs that let agents pay autonomously for compute.
AI-powered research and translation services for the Asian market — no other x402 provider covers Chinese/Japanese bilingual needs.
Development tools and utilities for x402.
Guides and tutorials for learning x402.
Video content about x402.
Written content about x402.
Connect with the x402 community.
